Safety and short-circuiting device for spark plugs



Sept. 2 1924. 1,507,391

C. K. MALOTT SAFETY AND SHORT CIRCiJITING DEVICE FOR SPARK PLUGS Filed June 12, 1920 #46155 N41. 077' Z2 6 K INVENTOR.

. ATTORNEY-5.

Patented Sept. 2, 1924.

UNITED STATES CHARLES K. MALOTT, OF INDIANAPOLIS, INDIANA.

SAFETY AND SHORT-CIRGUITING DEVICE FOR SPARK PLUGS.

Applicationfiled June 12, 1920. Serial No. 388,554.

To all whom it may concern:

Be it known that I, CHARLES K. MALorT, a citizen of the United States, and a resident of Indianapolis, county of Marion, and State of Indiana, have invented a certain new and useful Safety and ShortCircuiting Device for Spark Plugs; and I do hereby de clare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings, in which like numerals refer to like parts.

This invention relates to safety and short circuiting devices for spark plugs and the like.

The chief object of this invention is to provide means associated with the spark plug, which means may be used as a short circuiting device for the spark plug, and may also be used as a safety device for the spark plug, in the latter instance relieving the pressure upon the ignition system associated with the spark plug, should the same fail to operate in the usual manner.

One feature of the invention consists in associating the means for accomplishing the foregoing results with means for quickly attaching to or detaching from the spark plug the circuit means associated with the spark plug.

Another feature of the invention consists in associating with the circuit forming means suitable means whereby said circuit forming means is yieldingly maintained in an adjusted position for regulating the air gap between the spark plug and the circuit forming means.

A further feature of the invention consists in providing the supporting means with yielding means which are associated with suitable means formed upon the spark plug, so that the same is yieldingly maintained in an adjusted position upon the spark plug.

A further feature of the invention is the formation of the short circuiting lever or contact member such that the yielding support is adapted to. lock said lever or member in the short circuiting position upon the spark plug.

The full nature of the invention will be understood from the accompanying drawings and the. following description and claims.

In the drawings Fig. 1 is an elevational view of a spark plug showing the short circuiting and safety device attached thereto, said device being shown in side elevation and in an adjusted position. Fig. 2 is a similar view of the spark plug showing the device in end elevation. Fig. 3 is an enlarged side elevational view of the attachment. Fig. 41 is an enlarged end elevational view of the same. Fig. 5 is an enlarged sectional view through the pivot construction of the invention. Fig. 6 is a sectional plan view of the spark plug showing one feature of the invention. Fig. 7 is a central sectional view of the spark plug and another feature of the invention. Fig. 8 is a side elevational view of the short circuiting device in the short circuited and locked position.

In the drawings 10 indicates a standard spark plug provided with the usual exteriorly threaded body portion 11 by which the same is adapted to be secured into a cylinder of an internal combustion engine. The terminals of the standard spark plug are indicated by the numerals 12 and the means for securing the body portion 10 to the engine cylinder is the usual nut securing portion 18. The standard spark plug is also provided with the usual insulator 14: through which extendsthe usual central electrode 15, said central electrode and insulator being secured to the spark plug body portion 10 by the means 16, said means in this instance having a threaded portion 17 receivable by the spark plug body portion. The spark plug construction also is provided with the usual nut, contact or washer means 18 and the thumb nut 19 by which the circuit wire is secured to the central electrode, said wire being secured between the nut or washer 18 and the nut 19 in the usual manner.

To the spark plug, one form of which is shown in the drawings and numbered, is secured the invention. The invention is provided with means whereby the short circuit-- ing device is adapted to operate as a safety device. This safety feature consists of a parallel circuit from the body portion of the spark plug to the central electrode, which circuit is parallel to the circuit from the central electrode to the body portion of the spark plug, including the spark terminals 12 and the spark gap therebetween. Suitable means is associated with the short circuiting device such that the safety parallel circuit hereinbefore described includes an air gap the length of which is regulated by the means associated with said short circuiting means whereby the short circuiting means the current follows the normal path in the usual manner until such time as the spark plug fails to function in the customary manner. When-the spark plug fails to function, the current passes through the parallel circuit as described so as to relieve the ignition system from the pressure resulting from the non-actuation or failure of the spark plug. The safety feature of the short circuiting device, however, does not operate upon the usual spark plug when said spark plug short circuits within itself.

The safety and short circuiting attachment is shown in detail in Figs. 3 to 5 in elusive. As illustrated in Figs. 1 and 3 the circuit member 20 is provided with a con tact portion 21. The circuit member 20 is provided intermediate its ends with pivot forming means such as the cylindrical portion 22, drawn from the body portion of the circuit member 20, said drawn pivot being suitably supported by the means hereinafter to be described. v Upon the other end of the circuit member 20 is an actuating or handle portion 23. The handle portion 23 of the circuit member is positioned transversely of the body portion thereof, as shown clearly in Fig. 2. The handle portion and the drawn pivot are suitably formed upon the body portion by suitable die means customarily used in the metal art.

The means for pivotally supporting the toform a locking flange 27, whereby said body portion is pivotally supported upon said standard portion 24.

The means for yieldingly positioning the body portion in any adjusted position relative to the standard portion 24, and more particularly with respect to the spark plug, consists of cooperating means formed upon the standard portion and the body portion. In the present instance said cooperating means comprises a roughened surface 28 formed upon the body portion adjacent the bearingportion 25. The standard portion 24 and bearing portion 25 is suitably slotted at '29 to form a spring portion 30 integral with the bearing portion 25 and adapted to yieldingly engage the body portion 20 adj acent the roughened surface 28 to yieldingly maintain the circuit member 20 in any desired adjusted position.

The means for supporting the short circuiting device hereinbeforedescribed upon the spark plug in a novel and improved manner consists of a base portion 31. The base portion 31 comprises two angularly extending arm portions 32, whichare preferably formed integral with the standard por tion 24, and yet are separated from each other by means of the slot 33 formed in the standard portion 24. Each of the angularly positioned base portions 31 is curved arcuately so that both of said arm portions form a bifurcated construction which substantially encircles more than one-half of the spark plug circumference. The slot 33 in the standard portion, therefore, assisted by the twisting of the bearing portion 25 upon the standard 24 provides that said arms may be yieldingly positioned upon the spark plug and spread outwardly until said arms are seatable to substantially encircle said spark plug. Thus, the short circuiting' device is quickly'attachable to or detachable from the spark plug, said encircling bifurcated arms being receivable by the threaded portion of the spark plug or one of the other metal portions thereof.

In the present invention, however, suitable means is provided upon the spark plug to receive the encircling bifurcated arms 32. Said means comprises a circumferential groove 40 herein shown formed in the insulator securing member 16. The ,circum ferential groove 40, as shown clearly in Fig. 7 is provided with an annular offsetcha'nnel 41. Cooperating with the groove and channel means 40 and 41, respectively, are the free ends of the encircling bifurcated arms 32, said ends 34 being bent angularly to the main armportions such that the free ends thereof are seatable in the groove '40, and if desired, the depending ends may extend into the channel 41 when said ends are.

pointed. Inthe present form of the invention each of the bifurcated arms 32 adjacent the base portion 31 is provided with an angularly extending projection 35, said pro jection preferably being formed by prick punching the arm. Thus, the projection 35 and the free ends 34 are seated in the channel 41 and groove 40'and cooperate there with to yieldingly retain the standard porwith the channel and groove means formed in the spark plug.

In Fig. 8 the invention is illustrated in the short circuiting position when the parts are desired to be locked in said short circuiting position. The body member 20 ad j acent the beak portion 21 is provided with a cut away portion forming a notch 120 and a head portion 121. As shown clearly in Fig. 8, when the body portion is tilted into the short circuiting position, the same may be locked and maintained in a short circuiting position, such that the portion 21 of the body portion cooperates with the terminal means 18, and the notch 120 also cooperates therewith, so that the head portion 121 engages directly upon the means 18. When thus positioned, the body portion is held in position by the inherent spring tension of the standard portion 24, said portion moving outwardly away from the spark plug to permit said circuit member to be locked in the short circuiting position.

Nhen it is desired to move the circuit member to the non-actuating position, the same may be positioned as shown by the dotted lines in Fi 8. Then in this position, it will be understood that the device neither operates as a safety device nor operates as a short circuiting device until such time as the body portion is moved tothe adjusted safety position or the short circuiting position.

The invention claimed is:

1. A safety and short circuiting device for spark plugs, including a pivotally supported circuit member, standard means supporting said circuit member and supported upon said spark plug, and yielding means cooperating with said standard means and said circuit member to yieldingly maintain the latter in the desired adjusted position adjacent said spark plug.

2. The combination of a spark plug including a metallic portion provided with a circumferential groove, and a safety and short circuiting device for said spark plug, said device including a pivotally supported circuit member, standard means supporting said circuit member, and a bifurcated standard supporting base member, the free ends of said bifurcations extending angularly of said bifurcations and into said circumferential groove for yieldingly securing said safety and short circuiting device upon said spark plug.

3. The combination of a spark plug including a metallic portion provided with a circumferential groove, and an annular channel, a safety and short circuiting device for said spark plug, said device including a pivotally supported circuit member, standard means supporting said circuit member, a bifurcated standard supporting base member, the free ends of said bifurcations extending angularly of said bifurcations into said circumferential groove, and projecting means upon one of said bifurcations and sea-table in the annular channel for yieldingly securing said safety and short circuiting device upon said spark plug.

In witness whereof, I have hereunto affixed my signature.

CHARLES K. MALOTT. 

